US20170133852A1 - System and methods for power generation - Google Patents
System and methods for power generation Download PDFInfo
- Publication number
- US20170133852A1 US20170133852A1 US15/225,801 US201615225801A US2017133852A1 US 20170133852 A1 US20170133852 A1 US 20170133852A1 US 201615225801 A US201615225801 A US 201615225801A US 2017133852 A1 US2017133852 A1 US 2017133852A1
- Authority
- US
- United States
- Prior art keywords
- bus
- power
- power generation
- variable speed
- generation system
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 238000010248 power generation Methods 0.000 title claims abstract description 91
- 238000000034 method Methods 0.000 title claims description 24
- 238000004146 energy storage Methods 0.000 claims abstract description 70
- 239000000446 fuel Substances 0.000 claims description 20
- 239000003990 capacitor Substances 0.000 claims description 9
- 230000008859 change Effects 0.000 claims description 8
- 230000004044 response Effects 0.000 claims description 7
- 238000007599 discharging Methods 0.000 claims description 6
- 238000012544 monitoring process Methods 0.000 claims description 6
- 238000001914 filtration Methods 0.000 claims description 5
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 5
- 230000001131 transforming effect Effects 0.000 claims description 2
- 238000010586 diagram Methods 0.000 description 10
- 230000008901 benefit Effects 0.000 description 8
- 238000004891 communication Methods 0.000 description 4
- 230000009286 beneficial effect Effects 0.000 description 3
- 238000005553 drilling Methods 0.000 description 2
- 230000001502 supplementing effect Effects 0.000 description 2
- 230000001052 transient effect Effects 0.000 description 2
- 230000002457 bidirectional effect Effects 0.000 description 1
- 230000033228 biological regulation Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000005284 excitation Effects 0.000 description 1
- 230000008713 feedback mechanism Effects 0.000 description 1
- 238000009499 grossing Methods 0.000 description 1
- 230000006698 induction Effects 0.000 description 1
- 230000010354 integration Effects 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 239000003129 oil well Substances 0.000 description 1
- 238000005086 pumping Methods 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 238000009987 spinning Methods 0.000 description 1
- 230000000153 supplemental effect Effects 0.000 description 1
- 230000001360 synchronised effect Effects 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
- 238000004804 winding Methods 0.000 description 1
Images
Classifications
-
- H02J3/382—
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J3/00—Circuit arrangements for ac mains or ac distribution networks
- H02J3/38—Arrangements for parallely feeding a single network by two or more generators, converters or transformers
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J3/00—Circuit arrangements for ac mains or ac distribution networks
- H02J3/38—Arrangements for parallely feeding a single network by two or more generators, converters or transformers
- H02J3/381—Dispersed generators
-
- H02J3/383—
-
- H02J3/386—
-
- H02J3/387—
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J5/00—Circuit arrangements for transfer of electric power between ac networks and dc networks
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J7/00—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
- H02J7/34—Parallel operation in networks using both storage and other dc sources, e.g. providing buffering
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02K—DYNAMO-ELECTRIC MACHINES
- H02K7/00—Arrangements for handling mechanical energy structurally associated with dynamo-electric machines, e.g. structural association with mechanical driving motors or auxiliary dynamo-electric machines
- H02K7/18—Structural association of electric generators with mechanical driving motors, e.g. with turbines
- H02K7/1807—Rotary generators
- H02K7/1815—Rotary generators structurally associated with reciprocating piston engines
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M3/00—Conversion of dc power input into dc power output
- H02M3/02—Conversion of dc power input into dc power output without intermediate conversion into ac
- H02M3/04—Conversion of dc power input into dc power output without intermediate conversion into ac by static converters
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M7/00—Conversion of ac power input into dc power output; Conversion of dc power input into ac power output
- H02M7/02—Conversion of ac power input into dc power output without possibility of reversal
- H02M7/04—Conversion of ac power input into dc power output without possibility of reversal by static converters
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M7/00—Conversion of ac power input into dc power output; Conversion of dc power input into ac power output
- H02M7/42—Conversion of dc power input into ac power output without possibility of reversal
- H02M7/44—Conversion of dc power input into ac power output without possibility of reversal by static converters
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02P—CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS
- H02P7/00—Arrangements for regulating or controlling the speed or torque of electric DC motors
- H02P7/06—Arrangements for regulating or controlling the speed or torque of electric DC motors for regulating or controlling an individual dc dynamo-electric motor by varying field or armature current
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J2300/00—Systems for supplying or distributing electric power characterised by decentralized, dispersed, or local generation
- H02J2300/10—The dispersed energy generation being of fossil origin, e.g. diesel generators
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J2300/00—Systems for supplying or distributing electric power characterised by decentralized, dispersed, or local generation
- H02J2300/20—The dispersed energy generation being of renewable origin
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J2300/00—Systems for supplying or distributing electric power characterised by decentralized, dispersed, or local generation
- H02J2300/20—The dispersed energy generation being of renewable origin
- H02J2300/22—The renewable source being solar energy
- H02J2300/24—The renewable source being solar energy of photovoltaic origin
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J2300/00—Systems for supplying or distributing electric power characterised by decentralized, dispersed, or local generation
- H02J2300/20—The dispersed energy generation being of renewable origin
- H02J2300/28—The renewable source being wind energy
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J2300/00—Systems for supplying or distributing electric power characterised by decentralized, dispersed, or local generation
- H02J2300/30—The power source being a fuel cell
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J3/00—Circuit arrangements for ac mains or ac distribution networks
- H02J3/38—Arrangements for parallely feeding a single network by two or more generators, converters or transformers
- H02J3/388—Islanding, i.e. disconnection of local power supply from the network
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E10/00—Energy generation through renewable energy sources
- Y02E10/50—Photovoltaic [PV] energy
- Y02E10/56—Power conversion systems, e.g. maximum power point trackers
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E10/00—Energy generation through renewable energy sources
- Y02E10/70—Wind energy
- Y02E10/76—Power conversion electric or electronic aspects
Definitions
- the present technique relates generally to systems and methods for power generation, and more specifically, to power generation systems with variable power generation and energy storage.
- a power generation system can include a variable speed generation module with a variable speed generator coupled to an AC-DC converter; a power module (wherein the power module includes an energy storage unit coupled to a DC-DC converter and a DC-AC converter); an energy management system coupled to the variable speed generation module and the power module; a fixed speed generator; a DC bus wherein the variable speed generation module is coupled to the DC bus via the AC-DC converter, and the power module is coupled to the DC bus via the DC-DC converter and via the DC-AC converter; and an AC bus wherein the fixed speed generator is coupled to the AC bus via a breaker, and the AC bus is coupled to the DC bus via the DC-AC converter of the power module.
- the energy management system adjusts the electrical power output of the variable speed generator, the fixed speed generator, and the energy storage unit.
- the power generation system supplies DC power to at least one of a fixed DC load, a variable DC load, a motor, and/or the DC-AC converter. In other or the same embodiments, the power generation system supplies AC power to an AC load directly from the AC bus or from the DC bus via the DC-AC converter.
- the energy management system load-shares among the variable speed generator, the fixed speed generator, and the energy storage unit.
- a power generation system can also include a renewable energy source coupled to the DC bus.
- the renewable energy source can include a solar energy source, a wind turbine; and/or a water turbine.
- a power generation system can also include an alternative energy source coupled to the DC bus.
- the alternative energy source can include a fuel cell; and/or an exhaust gas-driven turbine-generator.
- the power generation system can also include an interface to a utility grid, wherein the interface is coupled to the AC bus.
- the energy storage unit includes at least one of a capacitor, an ultra-capacitor, and/or a battery.
- the variable speed generator is a permanent magnet generator.
- the energy management system operates the power generation system in island mode. In other, or the same embodiments, the energy management system operates the power generation system in micro-grid mode.
- the power generation system charges the energy storage unit.
- a method for operating a power generation system to generate electrical power can include: adjusting a speed of the variable speed generator to increase the fuel efficiency of the power generation system; adjusting the electrical power supplied by the energy storage unit in response to detecting a step load change; receiving a speed error from the variable speed generator, the speed error based at least in part on a difference between a commanded speed and a speed feedback value; filtering the speed error to generate a filtered speed error; receiving a DC bus voltage error based at least in part on a difference between a nominal DC bus voltage and a received DC bus voltage; selecting a control parameter based at least in part on the lower of the filtered speed error and the DC bus voltage error; receiving a variable speed generator error based at least in part on a difference between a desired variable speed generator load and a received load; combining the control parameter and the variable speed generator error to generate a current reference; discharging the energy storage unit of the power module based at least in part on the current reference; and/or charging the energy storage unit after the discharging the
- Adjusting the electrical power supplied by the energy storage unit can include monitoring a speed for the variable speed generator; monitoring a load on at least one of an AC bus and a DC bus; and/or governing the rate at which power is drawn from the energy storage unit based at least in part on the load.
- Charging the energy unit can include: determining an available power for charging based at least in part on a difference between a preferred load capacity at the present speed of the variable speed generator and a received load; transforming the available power for charging into a current reference limit; receiving a nominal source voltage error based at least in part on a difference between a desired voltage for the energy storage unit and a received voltage; generating a current reference based at least in part on the nominal source voltage error and the current reference limit; and charging the energy storage unit of the power module based at least in part on the current reference.
- filtering the speed error to generate a filtered speed error includes filtering the speed error using a Savitzky-Golay filter.
- FIG. 1 is a block diagram of a power generation system according to a first illustrated embodiment.
- FIG. 2 is a block diagram of a power generation system according to a second illustrated embodiment.
- FIG. 3 is a block diagram of a power generation system according to a third illustrated embodiment.
- FIG. 4 is a block diagram of a power generation system according to a fourth illustrated embodiment.
- FIG. 5 is a block diagram of a power generation system according to a fifth illustrated embodiment.
- FIG. 6A is a graph showing power plotted against speed for an example variable speed engine, such as the variable speed engine of FIGS. 1-5 .
- FIG. 6B is a graph showing Brake Specific Fuel Consumption (BSFC) plotted against load for an example embodiment of a hybrid power generation system such as the power generation system of FIG. 2 .
- BSFC Brake Specific Fuel Consumption
- FIG. 7 is a schematic illustrating PID control of the discharge of an energy storage device, such as one of the energy storage units of FIGS. 1-5 , during large step loads.
- FIG. 8 is a schematic illustrating PID control of the charging of an energy storage device, such as one of the energy storage units of FIGS. 1-5 .
- AFE Active Front End: actively converts between AC and DC power and can provide output voltage regulation and AC input harmonic reduction.
- An AFE is also referred to as an active rectifier.
- BSFC Fuel Specific Fuel Consumption: a measure of fuel efficiency for a prime mover that burns fuel and produces rotational power.
- EMS Electronic Management System: a system of tools to monitor, control and improve the performance of a power generation system.
- Fieldbus a family of network protocols for real-time distributed control (standardized as IEC 61158).
- Genset a combination of an electric generator and an engine.
- Inverter A DC-AC converter.
- a DC-AC converter For example, a device that converts direct current into alternating current. If the device is bidirectional, then it can also act as a rectifier and can convert alternating current into direct current.
- Island Mode Mode in which the variable speed generation module operates standalone with no fixed speed generators online.
- J1939 is a set of standards defined by the Society of Automotive Engineers (SAE), and the J1939 communication interface is a bus for communication and diagnostics that is typically used in vehicles.
- SAE Society of Automotive Engineers
- Micro-Grid Mode Mode in which the power generation system operates both variable speed and fixed speed generators at preferred loading points, generally to achieve improved fuel efficiency and reduced wear and tear on the engines.
- the mode also can reduce the number of fixed speed generators required to meet a given system capacity.
- Peak Shaving Reducing the amount of energy purchased from a utility during peak hours when the costs are higher than at another time.
- PID Proportional Integral Derivative Controller
- PMG Permanent Magnet Generator
- Savitzky-Golay filter A digital filter, applied to a set of digital data for the purpose of smoothing the data, that fits successive sub-sets of adjacent data points with a low-degree polynomial using the method of linear least squares.
- THD Total Harmonic Distortion
- Variable Speed Generator A generator that can run at a variable speed, generally as required to meet a given load.
- Power generation systems can be used to provide electrical power, including AC and DC power, for off-grid applications at remote sites.
- the power generation systems provide power for drilling and pumping operations at oil wells.
- a hybrid system comprising one or more engine-driven generators and energy storage, such as one or more battery banks, capacitor banks, or other suitable energy storage media, can be used to provide a reliable source of energy.
- Renewable energy sources, and/or other energy sources such as fuel cells, can also be used in the hybrid system as an alternative and/or secondary power source.
- a variable speed generator can be driven by an engine operating at an engine speed selected to meet the power demands of the load. Advantages of controlling engine speed to meet the load requirement can include improved performance, longer engine life, reduced fuel consumption, lower emissions, and reduced noise compared to a fixed speed generator.
- a power generation system can be operated using an energy management system comprising technology for monitoring, controlling, improving, and/or optimizing system performance.
- a hybrid variable speed/fixed speed power generation system with energy storage and energy management and corresponding methods for controlling hybrid power generation is described below.
- Benefits of the hybrid variable speed/fixed speed power generation system with energy storage and energy management and corresponding methods for controlling hybrid power generation include reduced fuel consumption and lower emissions, achieved by increasing efficiency and reducing the reliance on fixed speed diesel generators.
- the system comprises one or more variable speed generators and one or more fixed speed generators.
- the variable speed and fixed speed generators can be part of variable speed gensets and fixed speed gensets, respectively.
- variable speed gensets can each include a power source configured to operate at a variable rotor speed to provide responsive power to a load.
- the energy storage can be configured to store excess power and discharge power, as desired.
- At least some variable speed generators can provide power to a common DC bus via an AC-DC converter. At least some fixed speed generators can provide power to the AC Bus.
- An energy storage unit is connected to the common DC bus via a DC-DC converter.
- a motor can be connected to the common DC bus via an AC-DC converter.
- An alternative power source such as a fuel cell or an exhaust gas-driven turbine-generator, can also be connected to the DC bus via a DC-DC converter or an AC-DC converter, as appropriate.
- a renewable power source such as a wind turbine, can also be connected to the common DC bus via an AC-DC converter or a DC-DC converter.
- other types of power sources in addition to those specifically named can be connected to the common DC bus via an AC-DC converter or a DC-DC converter.
- other types of power sources in addition to those specifically named can be connected to an AC bus.
- the hybrid power generation system comprises a controller, known as an energy management system, communicatively coupled to the variable speed and fixed speed gensets, and the energy storage.
- the energy management system can improve, or optimize, system efficiency for different load profiles. In some embodiments, this is accomplished, at least in part, by utilizing the wide operating range of the variable speed generator to keep the fixed speed generator operating at a preferred, or optimal, load point.
- the generators can be controlled to allow the energy storage unit to charge when there is excess power available.
- the energy management system can adjust the power provided by the variable speed generator to meet the load requirements, and can start up/shut down the fixed speed generator.
- the energy management system can also control the use of the energy storage as a temporary source of power when the fixed speed generator is starting up.
- FIG. 1 is a block diagram of power generation system 100 , according to a first illustrated embodiment.
- Power generation system 100 comprises energy management system 110 , variable speed engine 120 , variable speed generation module 130 , and power module 140 .
- Energy management system (EMS) 110 controls variable speed engine 120 , variable speed generation module 130 , and power module 140 via interfaces 111 , 112 , and 113 , respectively.
- EMS 110 controls variable speed engine 120 via a J1939 communication interface, and controls variable speed generator module 130 and power module 140 via a Fieldbus interface.
- Variable speed engine 120 is operatively connected to variable speed generation module 130 .
- variable speed engine 120 is a diesel engine.
- Variable speed generation module 130 comprises variable speed generator 132 and inverter 134 .
- variable speed generator 132 is a permanent magnet generator (PMG). In other embodiments, variable speed generator 132 can be other suitable generators.
- inverter 134 is replaced by an active front end (AFE). Inverter 134 can be beneficial when variable speed generator 132 is a PMG or an induction generator. An AFE can be beneficial when variable speed generator 132 is a self-excited synchronous generator.
- Power generation system 100 further comprises DC bus 160 .
- Inverter 134 comprises an AC-DC converter. Inverter 134 converts variable voltage, variable frequency input to a fixed voltage DC for output to DC bus 160 .
- DC bus is in the range of 900 V to 1,000 V, for example 911 V. As indicated by arrow A, energy can flow in both directions between AFE 134 and DC bus 160 .
- Power generation system 100 provides DC power to motor 162 via DC bus 160 and DC-AC converter 164 .
- motor 162 can be a fan.
- Motor 162 can be one of the primary loads on a drilling rig.
- Power generation system 100 provides DC power to fixed and variable DC loads via DC bus 160 and DC-DC converter 168 .
- Power module 140 comprises DC-AC converter 142 , DC-DC converter 144 and energy storage units 146 .
- energy storage units 146 comprise at least one storage capacitor.
- energy storage units 146 can comprise at least one of ultra-capacitors and/or batteries.
- energy storage units 146 can comprise a motor/generator and flywheel combination and/or a motor/generator and compressed air combination, operatively connectable to DC bus 160 via a DC-AC inverter (not shown in FIG. 1 ).
- DC-DC converter 144 charges and discharges energy storage units 146 .
- EMS 110 controls power module 140 to supply energy to DC bus 160 via DC-DC converter 144 .
- system 100 can supply power to energy storage units 146 from at least one of variable speed generator 132 and AC bus 150 .
- Power generation system 100 further comprises AC bus 150 and customer AC loads, such as loads 152 and 154 . As indicated by arrow B, energy can flow in both directions between DC bus 160 and AC bus 150 via DC-AC converter 142 .
- DC-AC converter 142 provides AC power to AC bus 150 .
- DC-AC converter 142 can provide fixed voltage, fixed frequency AC. In some embodiments, DC-AC converter 142 can provide 600 V, 60 Hz, power to AC bus 150 with less than 5% THD. In some embodiments, example implementation, DC-AC converter 142 can provide power to AC bus 150 with 5% THD or greater.
- Power generation system 100 operates in island mode.
- EMS 110 controls system 100 by controlling variable speed engine 120 , variable speed generation module 130 and power module 140 .
- EMS 110 can monitor and manage customer AC loads 152 and 154 , if desired. EMS 110 can also monitor and manage motor 162 and customer DC loads 166 , if desired.
- Power module 140 of FIG. 1 is shown in conjunction with variable speed generation module 130 as part of system 100 . In other embodiments, power module 140 can operate as a standalone unit without being operatively connected to variable speed generation module 130 .
- Power module 140 can supply large amounts of power in a short time to support DC bus 160 , which in turn supports AC bus 150 . Power module 140 can provide the equivalent of a rotating reserve to DC bus 160 , even if variable speed generator 132 is off-line.
- FIG. 2 is a block diagram of power generation system 200 , according to a second illustrated embodiment.
- Power generation system 200 comprises the elements of power generation 100 .
- Power generation system 200 further comprises at least one fixed speed engine such as fixed speed engines 170 and 171 .
- Fixed speed engines 170 and 171 are operatively connected to fixed speed generators 172 and 173 , respectively.
- Fixed speed generators 172 and 173 provide power to AC bus 150 via breakers 174 and 175 , respectively.
- EMS 110 controls fixed speed engines 170 and 171 via interfaces 114 and 115 , respectively.
- EMS 110 controls fixed speed generators 172 and 173 , for example by start and stop commands.
- Loading of fixed speed generators 172 and 173 can be accomplished by monitoring the load on AC bus 150 , and adding to AC bus 150 , or subtracting from AC bus 150 , power supplied by variable speed generator module 130 via power module 140 . In this way, system 200 maintains a preferred, or optimal, load efficiency for most, if not all, connected generators.
- EMS 110 can switch power generation system 200 between island mode and micro-grid mode, according to system operation. In micro-grid mode, EMS 110 can blend operation of variable speed and fixed speed generators, generally to provide improved or optimal loading of the fixed speed generators.
- System 200 can control the load on the fixed speed generators by the degree to which it augments power on AC bus 150 using variable speed generator 132 and/or the energy storage units 146 .
- power generation system 200 has a total customer load of 2 MW.
- Variable speed generator 132 has a capacity of 1 MW.
- Fixed speed generators 172 and 173 also each have a capacity of 1 MW, and a preferred, or optimal, load of 850 kW. Operating each fixed speed generator at its optimal load of 850 kW would require variable speed generator 132 to provide the balance of 300 kW.
- EMS 110 adjusts the loading of the variable and fixed speed generators to reduce brake specific fuel consumption (BSFC). In some embodiments, it can be more efficient to operate the fixed speed generators each at 800 kW and the variable speed generator at 400 kW.
- BSFC brake specific fuel consumption
- fixed speed generator 173 can be shut down, and fixed speed generator 172 run at its preferred load of 850 kW, with variable speed generator 132 run at a load of 950 kW.
- it can be more efficient to run fixed speed generator 172 at a load of 900 kW and to run variable speed generator 132 at a load of 900 kW.
- EMS 110 can shut down variable speed generator 132 and run both fixed speed generators at a load of 900 kW each.
- a benefit of energy storage units 146 is that power generation system 200 can have less spinning reserve. Stored energy can be used, if needed, until system 200 brings another generator online. Power module 140 allows system 200 to operate as an uninterruptible power supply (UPS).
- UPS uninterruptible power supply
- system 200 can be used to recycle regenerated power for highly cyclical loads such as active heave winches.
- Overhauling load energy from AC bus 150 and DC bus 160 can be sent to energy storage units 146 , and then re-used when the load(s) become motoring.
- overhauling load energy from motor 162 can be sent to energy storage units 146 via DC-AC converter (inverter) 164 , DC bus 160 and DC-DC converter 144 . The overhauling load energy can then be re-used when the load becomes motoring.
- the load can increase from 1.8 MW to 2.2 MW when variable speed generator 132 is shut down (offline).
- the combined capacity of fixed speed generators 172 and 173 is only 2 MW which leaves a shortfall of 200 kW.
- EMS 110 can control system 100 such that the shortfall is supplied by stored energy from energy storage units 146 until another generator (either variable speed generator 132 or a third fixed speed generator not shown in FIG. 2 ) comes online.
- variable speed generator 132 or the third fixed speed generator can return to their preferred loading of 850 kW each.
- variable speed generator 132 of FIG. 1 can be omitted from power generation system 200 , such that power generation is provided by fixed speed generators only.
- FIG. 3 is a block diagram of power generation system 300 , according to a third illustrated embodiment.
- Power generation system 300 comprises the elements of power generation system 200 .
- Variable speed engine 120 , variable speed generation module 130 , variable speed generator 132 , and inverter 134 of FIG. 1 have been re-labeled 120 a, 130 a, 132 a, and 134 a, respectively.
- Power generation system 300 further comprises second variable speed engine 120 b, second variable speed generation module 130 b, second variable speed generator 132 b, and second inverter 134 b.
- EMS 110 controls variable speed engine 120 b and variable speed generation module 130 b via interfaces 118 and 119 , respectively.
- EMS 110 can control system 300 such that the load is shared efficiently between variable speed generators 120 a and 120 b, as well as between the variable and fixed speed generators.
- Power module 140 can provide support for multiple variable speed generators and thereby minimize, or at least reduce, the loading on the fixed speed generators.
- a benefit of power module 140 is that electrical generators on fixed speed generators 172 and 173 can be sized more modestly. For example, a 1 MW generator, conventionally sized to provide 1.25 MVA, can be fitted with a smaller electrical generator. It can also be used at close to unity power factor which reduces I 2 R losses in the windings and reduces field excitation losses, further improving efficiency of power generation system 300 .
- Power generation systems 100 , 200 , and 300 respectively support integration with optional renewable energy sources such as wind, water, and solar.
- FIG. 4 is a block diagram of power generation system 400 , according to a fourth illustrated embodiment.
- Power generation system 400 comprises the elements of power generation system 300 .
- Power generation system 400 further comprises solar or fuel cell energy source 180 and corresponding DC-DC converter 182 for supplying DC power to DC bus 160 .
- Power generation system 400 further comprises wind/water or exhaust gas-driven turbine-generator 184 and corresponding variable speed generator 186 and AFE 188 for supplying DC power to DC bus 160 .
- system 400 can supply power to energy storage units 146 from at least one of variable speed generator 132 , fixed speed generators 172 and 173 , AC bus 150 and renewable and/or alternative energy sources such as wind/water or exhaust gas-driven turbine-generator 184 and solar or fuel cell energy source 180 .
- FIG. 5 is a block diagram of power generation system 500 , according to a fifth illustrated embodiment.
- Power generation system 500 comprises the elements of power generation system 400 .
- Power generation system 500 further comprises a connection of AC bus 150 to grid 190 via breaker 176 .
- energy flows in both directions across the connection of AC bus 150 to grid 190 .
- grid 190 can supply energy to AC bus 150 and vice versa.
- EMS 110 can monitor and manage the connection to grid 190 .
- System 500 can operate in island mode, micro-grid mode and conventional AFE mode. In the latter mode, system 500 exports power to grid 190 .
- System 500 can adjust the amount of power drawn from grid 190 , including, for example, supplementing power from grid 190 with power from other elements of system 500 , such as variable and fixed speed generators, energy storage and renewable energy sources.
- EMS 110 of systems 100 - 500 of FIGS. 1-5 respectively, executes at least one method for operating systems 100 - 500 .
- the various methods can be chosen:
- FIG. 6A is a graph showing power plotted against speed for an example variable speed engine, such as variable speed engine 120 of FIGS. 1-5 .
- Load curve 610 is a plot of load capacity against speed for a generator i.e. a plot of the maximum load at a given engine speed. Load curve 610 can be specific to an engine and provided by the engine's manufacturer.
- Ideal BSFC load curve 620 is a plot of the load at which the generator is most fuel-efficient for a given speed. In some embodiments, BSFC curve 620 is derived from the fuel map. In some embodiments, BSFC curve 620 is derived from testing.
- Load curve 610 and BSFC curve 620 are inputs to EMS 110 and can be used in at least one method to obtain a preferred, or optimum, speed at which to run a variable speed generator given the present loading requirements of the system.
- the method can be selected to maintain a fuel-efficient speed in a variety of conditions while keeping the system stable.
- the system tracks the present load relative to load curve 610 and BSFC curve 620 .
- the system defines dead-band 630 on either side of ideal BSFC curve 620 within which changes in load do not trigger a change in speed of the variable speed generator.
- Dead-band 630 comprises upper bound 632 and lower bound 634 .
- An advantage of dead-band 630 is to prevent, or at least reduce, a response by the system to small load changes.
- Another advantage of dead-band 630 is that the system can operate more efficiently without making frequent speed changes in response to small load changes.
- the system responds by determining a new speed for the variable speed generator.
- the system commands the generator to adjust its speed to the new speed.
- the response can be supplemented by discharging at least one of the energy storage units.
- FIG. 6B is a graph showing Brake Specific Fuel Consumption (BSFC) plotted against load for an example embodiment of a hybrid power generation system such as power generation system of 200 FIG. 2 .
- BSFC Brake Specific Fuel Consumption
- Curve 650 shows BSFC versus load for a fixed speed generator such as fixed speed generator 172 of FIG. 2 .
- a fixed speed generator such as fixed speed generator 172 of FIG. 2
- Curve 660 shows BSFC versus load for a variable speed generator such as variable speed generator 132 of FIG. 2 .
- Curve 670 shows effective BSFC versus load for a combination of a fixed speed generator such as fixed speed generator 172 of FIG. 2 and a variable speed generator such as variable speed generator 132 of FIG. 2 .
- FIG. 6B illustrates the lower fuel consumption over the range of loads for the hybrid power generation system such as power generation system 200 of FIG. 2 .
- FIG. 7 is a schematic illustrating PID control of the discharge of an energy storage device, such as one of energy storage units 146 of FIGS. 1-5 , during large step loads.
- Speed error PID 710 monitors the drop in speed and uses a modified PID control method to generate a signal to module 740 .
- Speed error PID 710 can use unfiltered values for the input speed.
- the input values can be filtered. Since the input values can be noisy, it can be desirable to filter the values sufficiently to reduce noise without unduly affecting the ability of the system to respond to step load changes in a timely fashion.
- a Savitsky-Golay filter is used to filter speed values. In other embodiments, other suitable filters can be used to reduce noise.
- DC bus voltage error PID 720 monitors the drop in DC bus voltage and uses a modified PID control method to generate a signal to module 740 .
- Module 740 selects the lower of the two input signals and passes it to adder 745 . Since the signal is positive to charge and negative to discharge, the lower of the two input signals is the one that asks for the greater amount of power (i.e. the greater discharge from the energy storage units).
- the signal is moderated by signal from variable speed generator (VSG) loading error PID 730 .
- VSG variable speed generator
- the method illustrated in FIG. 7 allows the system to respond quickly to the large step load change while maintaining sufficient load on the VSG to avoid, or at least reduce the likelihood of, over-discharging the energy storage units.
- PID 730 receives a desired VSG load and a measured VSG load, and generates an error based on the difference between the desired and the measured VSG loads. PID 730 uses a modified PID control method to generate a signal sent to adder 745 .
- the system inputs the summed signal to DC-DC converter 750 attached to the energy storage units, and DC-DC converter 750 provides a determined amount of discharge in response to the step load change.
- the system re-charges the energy storage units.
- the charging is accomplished by increasing the load on the VSG without increasing the speed of the VSG.
- the system uses the margin between the BSFC curve and the load curve to increase VSG load without increasing speed.
- the margin between load curve 610 and BSFC curve 620 becomes smaller as the speed increases, so, at higher speeds, the system has less capacity to charge the energy storage units.
- the system determines a current reference charge limit by first selecting a load value between load curve 610 and BSFC curve 620 , and then translating the available load into a limiting value for the current reference.
- FIG. 6 shows available load curve 640 . Determining and applying a current reference charge limit is particularly beneficial at higher loads and higher speeds.
- FIG. 7 is a schematic illustrating PID control of the charging of an energy storage device, such as one of energy storage units 146 of FIGS. 1-5 .
- the system determines the available power for charging and the current reference limit.
- Nominal source voltage error PID 720 receives a desired capacitor voltage and a measured capacitor voltage, calculates an error, and uses a modified PID control method to determine the current reference.
- the current reference in this case, is positive because the system is charging.
- the limited current reference is sent to the DC-DC converter at 740 .
Landscapes
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Supply And Distribution Of Alternating Current (AREA)
- Control Of Eletrric Generators (AREA)
Abstract
A power generation system can include a variable speed generation module with a variable speed generator coupled to an AC-DC converter, a power module, an energy management system coupled to the variable speed generation module and the power module, a fixed speed generator, a DC bus wherein the variable speed generation module is coupled to a DC bus via the AC-DC converter, and the power module is coupled to the DC bus via the DC-DC converter and via the DC-AC converter, and an AC bus wherein the fixed speed generator is coupled to the AC bus via a breaker and the AC bus is coupled to the DC bus via the DC-AC converter of the power module wherein the energy management system adjusts the electrical power output of the variable speed generator, the fixed speed generator, and the energy storage unit.
Description
- This application claim priority benefits from U.S. provisional patent application No. 62/199,958 filed on Jul. 31, 2015 entitled “System and Methods for Power Generation”. The '958 application is incorporated by reference herein in its entirety.
- The present technique relates generally to systems and methods for power generation, and more specifically, to power generation systems with variable power generation and energy storage.
- A power generation system can include a variable speed generation module with a variable speed generator coupled to an AC-DC converter; a power module (wherein the power module includes an energy storage unit coupled to a DC-DC converter and a DC-AC converter); an energy management system coupled to the variable speed generation module and the power module; a fixed speed generator; a DC bus wherein the variable speed generation module is coupled to the DC bus via the AC-DC converter, and the power module is coupled to the DC bus via the DC-DC converter and via the DC-AC converter; and an AC bus wherein the fixed speed generator is coupled to the AC bus via a breaker, and the AC bus is coupled to the DC bus via the DC-AC converter of the power module. In some embodiments, the energy management system adjusts the electrical power output of the variable speed generator, the fixed speed generator, and the energy storage unit.
- In some embodiments, the power generation system supplies DC power to at least one of a fixed DC load, a variable DC load, a motor, and/or the DC-AC converter. In other or the same embodiments, the power generation system supplies AC power to an AC load directly from the AC bus or from the DC bus via the DC-AC converter.
- In certain embodiments, the energy management system load-shares among the variable speed generator, the fixed speed generator, and the energy storage unit.
- A power generation system can also include a renewable energy source coupled to the DC bus. The renewable energy source can include a solar energy source, a wind turbine; and/or a water turbine. A power generation system can also include an alternative energy source coupled to the DC bus. The alternative energy source can include a fuel cell; and/or an exhaust gas-driven turbine-generator.
- The power generation system can also include an interface to a utility grid, wherein the interface is coupled to the AC bus.
- In some embodiments, the energy storage unit includes at least one of a capacitor, an ultra-capacitor, and/or a battery. In certain embodiments, the variable speed generator is a permanent magnet generator.
- In at least some embodiments, the energy management system operates the power generation system in island mode. In other, or the same embodiments, the energy management system operates the power generation system in micro-grid mode.
- In some embodiments, the power generation system charges the energy storage unit.
- A method for operating a power generation system to generate electrical power can include: adjusting a speed of the variable speed generator to increase the fuel efficiency of the power generation system; adjusting the electrical power supplied by the energy storage unit in response to detecting a step load change; receiving a speed error from the variable speed generator, the speed error based at least in part on a difference between a commanded speed and a speed feedback value; filtering the speed error to generate a filtered speed error; receiving a DC bus voltage error based at least in part on a difference between a nominal DC bus voltage and a received DC bus voltage; selecting a control parameter based at least in part on the lower of the filtered speed error and the DC bus voltage error; receiving a variable speed generator error based at least in part on a difference between a desired variable speed generator load and a received load; combining the control parameter and the variable speed generator error to generate a current reference; discharging the energy storage unit of the power module based at least in part on the current reference; and/or charging the energy storage unit after the discharging the energy storage unit.
- Adjusting the electrical power supplied by the energy storage unit can include monitoring a speed for the variable speed generator; monitoring a load on at least one of an AC bus and a DC bus; and/or governing the rate at which power is drawn from the energy storage unit based at least in part on the load.
- Charging the energy unit can include: determining an available power for charging based at least in part on a difference between a preferred load capacity at the present speed of the variable speed generator and a received load; transforming the available power for charging into a current reference limit; receiving a nominal source voltage error based at least in part on a difference between a desired voltage for the energy storage unit and a received voltage; generating a current reference based at least in part on the nominal source voltage error and the current reference limit; and charging the energy storage unit of the power module based at least in part on the current reference.
- In some embodiments, filtering the speed error to generate a filtered speed error includes filtering the speed error using a Savitzky-Golay filter.
-
FIG. 1 is a block diagram of a power generation system according to a first illustrated embodiment. -
FIG. 2 is a block diagram of a power generation system according to a second illustrated embodiment. -
FIG. 3 is a block diagram of a power generation system according to a third illustrated embodiment. -
FIG. 4 is a block diagram of a power generation system according to a fourth illustrated embodiment. -
FIG. 5 is a block diagram of a power generation system according to a fifth illustrated embodiment. -
FIG. 6A is a graph showing power plotted against speed for an example variable speed engine, such as the variable speed engine ofFIGS. 1-5 . -
FIG. 6B is a graph showing Brake Specific Fuel Consumption (BSFC) plotted against load for an example embodiment of a hybrid power generation system such as the power generation system ofFIG. 2 . -
FIG. 7 is a schematic illustrating PID control of the discharge of an energy storage device, such as one of the energy storage units ofFIGS. 1-5 , during large step loads. -
FIG. 8 is a schematic illustrating PID control of the charging of an energy storage device, such as one of the energy storage units ofFIGS. 1-5 . - AFE (Active Front End): actively converts between AC and DC power and can provide output voltage regulation and AC input harmonic reduction. An AFE is also referred to as an active rectifier.
- BSFC (Brake Specific Fuel Consumption): a measure of fuel efficiency for a prime mover that burns fuel and produces rotational power.
- EMS (Energy Management System): a system of tools to monitor, control and improve the performance of a power generation system.
- Fieldbus: a family of network protocols for real-time distributed control (standardized as IEC 61158).
- Genset: a combination of an electric generator and an engine.
- Inverter: A DC-AC converter. For example, a device that converts direct current into alternating current. If the device is bidirectional, then it can also act as a rectifier and can convert alternating current into direct current.
- Island Mode: Mode in which the variable speed generation module operates standalone with no fixed speed generators online.
- J1939 communication interface: J1939 is a set of standards defined by the Society of Automotive Engineers (SAE), and the J1939 communication interface is a bus for communication and diagnostics that is typically used in vehicles.
- Micro-Grid Mode: Mode in which the power generation system operates both variable speed and fixed speed generators at preferred loading points, generally to achieve improved fuel efficiency and reduced wear and tear on the engines. The mode also can reduce the number of fixed speed generators required to meet a given system capacity.
- Peak Shaving: Reducing the amount of energy purchased from a utility during peak hours when the costs are higher than at another time.
- PID (Proportional Integral Derivative) Controller: A control loop feedback mechanism that calculates and attempts to minimize, or at least reduce a difference between a measured value and a desired setpoint.
- PMG (Permanent Magnet Generator): A generator where at least one permanent magnet provides the magnetic field of the rotor.
- Savitzky-Golay filter: A digital filter, applied to a set of digital data for the purpose of smoothing the data, that fits successive sub-sets of adjacent data points with a low-degree polynomial using the method of linear least squares.
- THD (Total Harmonic Distortion): The ratio of the sum of the powers of all harmonic components to the power of the fundamental frequency. THD is a measure of the power quality of electric power systems.
- Variable Speed Generator: A generator that can run at a variable speed, generally as required to meet a given load.
- Power generation systems can be used to provide electrical power, including AC and DC power, for off-grid applications at remote sites. In some examples the power generation systems provide power for drilling and pumping operations at oil wells. A hybrid system comprising one or more engine-driven generators and energy storage, such as one or more battery banks, capacitor banks, or other suitable energy storage media, can be used to provide a reliable source of energy. Renewable energy sources, and/or other energy sources such as fuel cells, can also be used in the hybrid system as an alternative and/or secondary power source.
- A variable speed generator can be driven by an engine operating at an engine speed selected to meet the power demands of the load. Advantages of controlling engine speed to meet the load requirement can include improved performance, longer engine life, reduced fuel consumption, lower emissions, and reduced noise compared to a fixed speed generator. A power generation system can be operated using an energy management system comprising technology for monitoring, controlling, improving, and/or optimizing system performance.
- A hybrid variable speed/fixed speed power generation system with energy storage and energy management and corresponding methods for controlling hybrid power generation is described below.
- Benefits of the hybrid variable speed/fixed speed power generation system with energy storage and energy management and corresponding methods for controlling hybrid power generation include reduced fuel consumption and lower emissions, achieved by increasing efficiency and reducing the reliance on fixed speed diesel generators.
- In at least one embodiment, the system comprises one or more variable speed generators and one or more fixed speed generators. The variable speed and fixed speed generators can be part of variable speed gensets and fixed speed gensets, respectively.
- The variable speed gensets can each include a power source configured to operate at a variable rotor speed to provide responsive power to a load. The energy storage can be configured to store excess power and discharge power, as desired.
- At least some variable speed generators can provide power to a common DC bus via an AC-DC converter. At least some fixed speed generators can provide power to the AC Bus. An energy storage unit is connected to the common DC bus via a DC-DC converter. A motor can be connected to the common DC bus via an AC-DC converter. An alternative power source, such as a fuel cell or an exhaust gas-driven turbine-generator, can also be connected to the DC bus via a DC-DC converter or an AC-DC converter, as appropriate. A renewable power source, such as a wind turbine, can also be connected to the common DC bus via an AC-DC converter or a DC-DC converter. In some embodiments, other types of power sources in addition to those specifically named can be connected to the common DC bus via an AC-DC converter or a DC-DC converter. Similarly, in other or the same embodiments, other types of power sources in addition to those specifically named can be connected to an AC bus.
- The hybrid power generation system comprises a controller, known as an energy management system, communicatively coupled to the variable speed and fixed speed gensets, and the energy storage. The energy management system can improve, or optimize, system efficiency for different load profiles. In some embodiments, this is accomplished, at least in part, by utilizing the wide operating range of the variable speed generator to keep the fixed speed generator operating at a preferred, or optimal, load point.
- The generators can be controlled to allow the energy storage unit to charge when there is excess power available.
- The energy management system can adjust the power provided by the variable speed generator to meet the load requirements, and can start up/shut down the fixed speed generator. The energy management system can also control the use of the energy storage as a temporary source of power when the fixed speed generator is starting up.
-
FIG. 1 is a block diagram ofpower generation system 100, according to a first illustrated embodiment. -
Power generation system 100 comprisesenergy management system 110,variable speed engine 120, variablespeed generation module 130, andpower module 140. - Energy management system (EMS) 110 controls
variable speed engine 120, variablespeed generation module 130, andpower module 140 viainterfaces EMS 110 controlsvariable speed engine 120 via a J1939 communication interface, and controls variablespeed generator module 130 andpower module 140 via a Fieldbus interface. -
Variable speed engine 120 is operatively connected to variablespeed generation module 130. In at least one embodiment,variable speed engine 120 is a diesel engine. - Variable
speed generation module 130 comprisesvariable speed generator 132 andinverter 134. - In at least one embodiment,
variable speed generator 132 is a permanent magnet generator (PMG). In other embodiments,variable speed generator 132 can be other suitable generators. In at least one embodiment,inverter 134 is replaced by an active front end (AFE).Inverter 134 can be beneficial whenvariable speed generator 132 is a PMG or an induction generator. An AFE can be beneficial whenvariable speed generator 132 is a self-excited synchronous generator. -
Power generation system 100 further comprisesDC bus 160.Inverter 134 comprises an AC-DC converter.Inverter 134 converts variable voltage, variable frequency input to a fixed voltage DC for output toDC bus 160. In at least one embodiment, DC bus is in the range of 900 V to 1,000 V, for example 911 V. As indicated by arrow A, energy can flow in both directions betweenAFE 134 andDC bus 160. -
Power generation system 100 provides DC power tomotor 162 viaDC bus 160 and DC-AC converter 164. In some embodiments,motor 162 can be a fan.Motor 162 can be one of the primary loads on a drilling rig.Power generation system 100 provides DC power to fixed and variable DC loads viaDC bus 160 and DC-DC converter 168. -
Power module 140 comprises DC-AC converter 142, DC-DC converter 144 andenergy storage units 146. In some embodiments,energy storage units 146 comprise at least one storage capacitor. In other embodiments,energy storage units 146 can comprise at least one of ultra-capacitors and/or batteries. In yet other embodiments,energy storage units 146 can comprise a motor/generator and flywheel combination and/or a motor/generator and compressed air combination, operatively connectable toDC bus 160 via a DC-AC inverter (not shown inFIG. 1 ). - As indicated by arrow C, energy can flow in both directions between
DC bus 160 andenergy storage units 146 via DC-DC converter 144. DC-DC converter 144 charges and dischargesenergy storage units 146. -
EMS 110 controlspower module 140 to supply energy toDC bus 160 via DC-DC converter 144. Under the control ofEMS 110,system 100 can supply power toenergy storage units 146 from at least one ofvariable speed generator 132 andAC bus 150. -
Power generation system 100 further comprisesAC bus 150 and customer AC loads, such asloads DC bus 160 andAC bus 150 via DC-AC converter 142. In at least one mode of operation, DC-AC converter 142 provides AC power toAC bus 150. DC-AC converter 142 can provide fixed voltage, fixed frequency AC. In some embodiments, DC-AC converter 142 can provide 600 V, 60 Hz, power toAC bus 150 with less than 5% THD. In some embodiments, example implementation, DC-AC converter 142 can provide power toAC bus 150 with 5% THD or greater. -
Power generation system 100 operates in island mode.EMS 110controls system 100 by controllingvariable speed engine 120, variablespeed generation module 130 andpower module 140. -
EMS 110 can monitor and manage customer AC loads 152 and 154, if desired.EMS 110 can also monitor and managemotor 162 and customer DC loads 166, if desired. -
Power module 140 ofFIG. 1 is shown in conjunction with variablespeed generation module 130 as part ofsystem 100. In other embodiments,power module 140 can operate as a standalone unit without being operatively connected to variablespeed generation module 130. -
Power module 140 can supply large amounts of power in a short time to supportDC bus 160, which in turn supportsAC bus 150.Power module 140 can provide the equivalent of a rotating reserve toDC bus 160, even ifvariable speed generator 132 is off-line. -
FIG. 2 is a block diagram ofpower generation system 200, according to a second illustrated embodiment. -
Power generation system 200 comprises the elements ofpower generation 100.Power generation system 200 further comprises at least one fixed speed engine such as fixedspeed engines Fixed speed engines speed generators Fixed speed generators AC bus 150 viabreakers -
EMS 110 controls fixedspeed engines interfaces EMS 110 controls fixedspeed generators speed generators AC bus 150, and adding toAC bus 150, or subtracting fromAC bus 150, power supplied by variablespeed generator module 130 viapower module 140. In this way,system 200 maintains a preferred, or optimal, load efficiency for most, if not all, connected generators. -
EMS 110 can switchpower generation system 200 between island mode and micro-grid mode, according to system operation. In micro-grid mode,EMS 110 can blend operation of variable speed and fixed speed generators, generally to provide improved or optimal loading of the fixed speed generators. -
System 200 can control the load on the fixed speed generators by the degree to which it augments power onAC bus 150 usingvariable speed generator 132 and/or theenergy storage units 146. - In one example
power generation system 200 has a total customer load of 2 MW.Variable speed generator 132 has a capacity of 1 MW.Fixed speed generators variable speed generator 132 to provide the balance of 300 kW. -
EMS 110 adjusts the loading of the variable and fixed speed generators to reduce brake specific fuel consumption (BSFC). In some embodiments, it can be more efficient to operate the fixed speed generators each at 800 kW and the variable speed generator at 400 kW. - If the load reduces from 2 MW to 1.8 MW, for example, then fixed
speed generator 173 can be shut down, and fixedspeed generator 172 run at its preferred load of 850 kW, withvariable speed generator 132 run at a load of 950 kW. Alternatively, in some embodiments, it can be more efficient to run fixedspeed generator 172 at a load of 900 kW and to runvariable speed generator 132 at a load of 900 kW. In yet another alternative scenario,EMS 110 can shut downvariable speed generator 132 and run both fixed speed generators at a load of 900 kW each. - A benefit of
energy storage units 146 is thatpower generation system 200 can have less spinning reserve. Stored energy can be used, if needed, untilsystem 200 brings another generator online.Power module 140 allowssystem 200 to operate as an uninterruptible power supply (UPS). - In some cases,
system 200 can be used to recycle regenerated power for highly cyclical loads such as active heave winches. Overhauling load energy fromAC bus 150 andDC bus 160 can be sent toenergy storage units 146, and then re-used when the load(s) become motoring. For example, overhauling load energy frommotor 162 can be sent toenergy storage units 146 via DC-AC converter (inverter) 164,DC bus 160 and DC-DC converter 144. The overhauling load energy can then be re-used when the load becomes motoring. - In another example the load can increase from 1.8 MW to 2.2 MW when
variable speed generator 132 is shut down (offline). The combined capacity of fixedspeed generators EMS 110 can controlsystem 100 such that the shortfall is supplied by stored energy fromenergy storage units 146 until another generator (eithervariable speed generator 132 or a third fixed speed generator not shown inFIG. 2 ) comes online. - Once
variable speed generator 132 or the third fixed speed generator is online, fixedspeed generators - In other embodiments,
variable speed generator 132 ofFIG. 1 can be omitted frompower generation system 200, such that power generation is provided by fixed speed generators only. -
FIG. 3 is a block diagram ofpower generation system 300, according to a third illustrated embodiment. -
Power generation system 300 comprises the elements ofpower generation system 200.Variable speed engine 120, variablespeed generation module 130,variable speed generator 132, andinverter 134 ofFIG. 1 , have been re-labeled 120 a, 130 a, 132 a, and 134 a, respectively.Power generation system 300 further comprises secondvariable speed engine 120 b, second variablespeed generation module 130 b, secondvariable speed generator 132 b, andsecond inverter 134 b. -
EMS 110 controlsvariable speed engine 120 b and variablespeed generation module 130 b viainterfaces -
EMS 110 can controlsystem 300 such that the load is shared efficiently betweenvariable speed generators Power module 140 can provide support for multiple variable speed generators and thereby minimize, or at least reduce, the loading on the fixed speed generators. - A benefit of
power module 140 is that electrical generators on fixedspeed generators power generation system 300. -
Power generation systems -
FIG. 4 is a block diagram ofpower generation system 400, according to a fourth illustrated embodiment.Power generation system 400 comprises the elements ofpower generation system 300.Power generation system 400 further comprises solar or fuelcell energy source 180 and corresponding DC-DC converter 182 for supplying DC power toDC bus 160.Power generation system 400 further comprises wind/water or exhaust gas-driven turbine-generator 184 and correspondingvariable speed generator 186 andAFE 188 for supplying DC power toDC bus 160. - Under the control of
EMS 110,system 400 can supply power toenergy storage units 146 from at least one ofvariable speed generator 132, fixedspeed generators AC bus 150 and renewable and/or alternative energy sources such as wind/water or exhaust gas-driven turbine-generator 184 and solar or fuelcell energy source 180. -
FIG. 5 is a block diagram ofpower generation system 500, according to a fifth illustrated embodiment. -
Power generation system 500 comprises the elements ofpower generation system 400.Power generation system 500 further comprises a connection ofAC bus 150 togrid 190 viabreaker 176. As indicated by arrow H, energy flows in both directions across the connection ofAC bus 150 togrid 190. In some embodiments,grid 190 can supply energy toAC bus 150 and vice versa. -
EMS 110 can monitor and manage the connection togrid 190.System 500 can operate in island mode, micro-grid mode and conventional AFE mode. In the latter mode,system 500 exports power togrid 190. - A benefit of
system 500 is that it provides an opportunity for peak shaving.System 500 can adjust the amount of power drawn fromgrid 190, including, for example, supplementing power fromgrid 190 with power from other elements ofsystem 500, such as variable and fixed speed generators, energy storage and renewable energy sources. -
EMS 110 of systems 100-500 ofFIGS. 1-5 , respectively, executes at least one method for operating systems 100-500. The various methods can be chosen: -
- a) to operate variable speed generator 120 (or
generators - b) to respond to high step load changes by supplementing power via
energy storage units 146; - c) to reduce, or minimize, the use of stored energy by governing the rate at which supplemental energy is supplied during conditions in which the system is under transient load demand;
- d) to increase, or optimize, the rate of charging of
energy storage units 146; - e) to maintain improved, or optimal, loading on fixed
speed generators - f) to maintain high quality power on the AC Bus (for example, to reduce, or minimize, voltage deviation and frequency deviation during transient load conditions).
- a) to operate variable speed generator 120 (or
-
FIG. 6A is a graph showing power plotted against speed for an example variable speed engine, such asvariable speed engine 120 ofFIGS. 1-5 .Load curve 610 is a plot of load capacity against speed for a generator i.e. a plot of the maximum load at a given engine speed.Load curve 610 can be specific to an engine and provided by the engine's manufacturer. IdealBSFC load curve 620 is a plot of the load at which the generator is most fuel-efficient for a given speed. In some embodiments,BSFC curve 620 is derived from the fuel map. In some embodiments,BSFC curve 620 is derived from testing. -
Load curve 610 andBSFC curve 620 are inputs toEMS 110 and can be used in at least one method to obtain a preferred, or optimum, speed at which to run a variable speed generator given the present loading requirements of the system. The method can be selected to maintain a fuel-efficient speed in a variety of conditions while keeping the system stable. - The system tracks the present load relative to load
curve 610 andBSFC curve 620. The system defines dead-band 630 on either side ofideal BSFC curve 620 within which changes in load do not trigger a change in speed of the variable speed generator. Dead-band 630 comprises upper bound 632 and lower bound 634. An advantage of dead-band 630 is to prevent, or at least reduce, a response by the system to small load changes. Another advantage of dead-band 630 is that the system can operate more efficiently without making frequent speed changes in response to small load changes. - When a load change occurs, and the load is outside dead-
band 630, the system responds by determining a new speed for the variable speed generator. The system commands the generator to adjust its speed to the new speed. The response can be supplemented by discharging at least one of the energy storage units. -
FIG. 6B is a graph showing Brake Specific Fuel Consumption (BSFC) plotted against load for an example embodiment of a hybrid power generation system such as power generation system of 200FIG. 2 . -
Curve 650 shows BSFC versus load for a fixed speed generator such as fixedspeed generator 172 ofFIG. 2 . In the example shown inFIG. 6B , it can be desirable to maintain operation of the fixed speed generator at a load of about 400 kW to 600 kW.Curve 660 shows BSFC versus load for a variable speed generator such asvariable speed generator 132 ofFIG. 2 .Curve 670 shows effective BSFC versus load for a combination of a fixed speed generator such as fixedspeed generator 172 ofFIG. 2 and a variable speed generator such asvariable speed generator 132 ofFIG. 2 .FIG. 6B illustrates the lower fuel consumption over the range of loads for the hybrid power generation system such aspower generation system 200 ofFIG. 2 . -
FIG. 7 is a schematic illustrating PID control of the discharge of an energy storage device, such as one ofenergy storage units 146 ofFIGS. 1-5 , during large step loads. - When a large step load change occurs, a diesel engine, unable to respond immediately, will experience a drop in speed. If the drop in speed is too great, the diesel engine will stall.
Speed error PID 710 monitors the drop in speed and uses a modified PID control method to generate a signal tomodule 740. -
Speed error PID 710 can use unfiltered values for the input speed. Alternatively, the input values can be filtered. Since the input values can be noisy, it can be desirable to filter the values sufficiently to reduce noise without unduly affecting the ability of the system to respond to step load changes in a timely fashion. In at least one embodiment, a Savitsky-Golay filter is used to filter speed values. In other embodiments, other suitable filters can be used to reduce noise. - In response to the large step load change, the AC-DC converter, responsible for converting AC power into power for the DC bus, can have insufficient energy to maintain the DC bus voltage, resulting in a drop in DC bus voltage. DC bus
voltage error PID 720 monitors the drop in DC bus voltage and uses a modified PID control method to generate a signal tomodule 740. -
Module 740 selects the lower of the two input signals and passes it to adder 745. Since the signal is positive to charge and negative to discharge, the lower of the two input signals is the one that asks for the greater amount of power (i.e. the greater discharge from the energy storage units). - At
adder 745, the signal is moderated by signal from variable speed generator (VSG)loading error PID 730. The method illustrated inFIG. 7 allows the system to respond quickly to the large step load change while maintaining sufficient load on the VSG to avoid, or at least reduce the likelihood of, over-discharging the energy storage units. -
PID 730 receives a desired VSG load and a measured VSG load, and generates an error based on the difference between the desired and the measured VSG loads.PID 730 uses a modified PID control method to generate a signal sent to adder 745. - The system inputs the summed signal to DC-
DC converter 750 attached to the energy storage units, and DC-DC converter 750 provides a determined amount of discharge in response to the step load change. - Once the energy storage units have depleted some of their charge, and the system is within dead-
band 630 of idealBSFC load curve 620 ofFIG. 6 , then the system re-charges the energy storage units. The charging is accomplished by increasing the load on the VSG without increasing the speed of the VSG. The system uses the margin between the BSFC curve and the load curve to increase VSG load without increasing speed. - Referring again to
FIG. 6 , the margin betweenload curve 610 andBSFC curve 620 becomes smaller as the speed increases, so, at higher speeds, the system has less capacity to charge the energy storage units. The system determines a current reference charge limit by first selecting a load value betweenload curve 610 andBSFC curve 620, and then translating the available load into a limiting value for the current reference.FIG. 6 showsavailable load curve 640. Determining and applying a current reference charge limit is particularly beneficial at higher loads and higher speeds. -
FIG. 7 is a schematic illustrating PID control of the charging of an energy storage device, such as one ofenergy storage units 146 ofFIGS. 1-5 . Inmodule 710, the system determines the available power for charging and the current reference limit. Nominal sourcevoltage error PID 720 receives a desired capacitor voltage and a measured capacitor voltage, calculates an error, and uses a modified PID control method to determine the current reference. The current reference, in this case, is positive because the system is charging. The limited current reference is sent to the DC-DC converter at 740. - While particular elements, embodiments and applications of the present invention have been shown and described, it will be understood, that the invention is not limited thereto since modifications can be made by those skilled in the art without departing from the scope of the present disclosure, particularly in light of the foregoing teachings.
Claims (20)
1. A power generation system comprising:
a. a variable speed generation module with a variable speed generator coupled to an AC-DC converter;
b. a power module comprising:
i. an energy storage unit coupled to a DC-DC converter; and
ii. a DC-AC converter,
c. an energy management system coupled to said variable speed generation module and said power module;
d. a fixed speed generator;
e. a DC bus wherein said variable speed generation module is coupled to said DC bus via said AC-DC converter, and said power module is coupled to said DC bus via said DC-DC converter and via said DC-AC converter; and
f. an AC bus wherein said fixed speed generator is coupled to said AC bus via a breaker, and said AC bus is coupled to said DC bus via said DC-AC converter of said power module, wherein said energy management system adjusts the electrical power output of said variable speed generator, said fixed speed generator, and said energy storage unit.
2. The power generation system of claim 1 wherein said power generation system supplies DC power to at least one of the group consisting of a fixed DC load, a variable DC load, a motor, and said DC-AC converter.
3. The power generation system of claim 1 wherein said power generation system supplies AC power to an AC load directly from said AC bus or via said DC-AC converter.
4. The power generation system of claim 1 wherein said energy management system load-shares among said variable speed generator, said fixed speed generator, and said energy storage unit.
5. The power generation system of claim 1 further comprising
g. a renewable energy source coupled to said DC bus.
6. The power generation system of claim 5 wherein renewable energy source comprises at least one from the group consisting of a solar energy source, a wind turbine; and a water turbine.
7. The power generation system of claim 1 further comprising
g. an alternative energy source coupled to said DC bus.
8. The power generation system of claim 7 wherein the alternative energy source comprises at least one from the group consisting of a fuel cell and an exhaust gas-driven turbine-generator.
9. The power generation system of claim 1 further comprising:
g. an interface to a utility grid, said interface coupled to said AC bus.
10. The power generation system of claim 1 wherein said energy storage unit comprises at least one from the group consisting of a capacitor, an ultra-capacitor, and a battery.
11. The power generation system of claim 1 wherein said variable speed generator is a permanent magnet generator.
12. The power generation system of claim 1 wherein said energy management system operates said power generation system in island mode.
13. The power generation system of claim 1 wherein said energy management system operates said power generation system in micro-grid mode.
14. The power generation system of claim 1 wherein said power generation system charges said energy storage unit.
15. A method for operating a power generation system to generate electrical power wherein said power generation system comprises:
a. a variable speed generation module with a variable speed generator coupled to an AC-DC converter;
b. a power module comprising:
i. an energy storage unit coupled to a DC-DC converter; and
ii. a DC-AC converter,
c. an energy management system coupled to said variable speed generation module and said power module;
d. a fixed speed generator;
e. a DC bus wherein said variable speed generation module is coupled to said DC bus via said AC-DC converter, and said power module is coupled to said DC bus via said DC-DC converter and via said DC-AC converter; and
f. an AC bus wherein said fixed speed generator is coupled to said AC bus via a breaker, and said AC bus is coupled to said DC bus via said DC-AC converter of said power module, wherein said energy management system adjusts the electrical power output of said variable speed generator, said fixed speed generator, and said energy storage unit; and
wherein said method comprises:
a. adjusting a speed of said variable speed generator to increase the fuel efficiency of said power generation system.
16. The method of claim 15 further comprising:
b. adjusting the electrical power supplied by said energy storage unit in response to detecting a step load change.
17. The method of claim 16 wherein adjusting the electrical power supplied by said energy storage unit includes:
i. monitoring a speed of said variable speed generator;
ii. monitoring a load on at least one of an AC bus and a DC bus;
iii. adjusting the speed of said at least one variable speed generator, based at least in part on said load; and
iv. governing the rate at which power is drawn from said energy storage unit, based at least in part on said load.
18. The method of claim 15 further comprising:
b. receiving a speed error from said variable speed generator, said speed error based at least in part on a difference between a commanded speed and a speed feedback value;
c. filtering said speed error to generate a filtered speed error;
d. receiving a DC bus voltage error based at least in part on a difference between a nominal DC bus voltage and a received DC bus voltage;
e. selecting a control parameter based at least in part on the lower of said filtered speed error and said DC bus voltage error;
f. receiving a variable speed generator error based at least in part on a difference between a desired variable speed generator load and a received load;
g. combining said control parameter and said variable speed generator error to generate a current reference; and
h. discharging said energy storage unit of said power module based at least in part on said current reference.
19. The method of claim 18 further comprising:
i. charging said energy storage unit after said discharging said energy storage unit, said charging comprising;
i. determining an available power for charging based at least in part on a difference between a preferred load capacity at the present speed of said variable speed generator and a received load;
ii. transforming said available power for charging into a current reference limit;
iii. receiving a nominal source voltage error based at least in part on a difference between a desired voltage for said energy storage unit and a received voltage;
iv. generating a current reference based at least in part on said nominal source voltage error and said current reference limit; and
v. charging said energy storage unit of said power module based at least in part on said current reference.
20. The method of claim 18 wherein filtering said speed error utilizes a Savitzky-Golay filter.
Priority Applications (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US15/225,801 US10283966B2 (en) | 2015-07-31 | 2016-08-01 | System and methods for power generation |
US16/370,367 US20190229534A1 (en) | 2015-07-31 | 2019-03-29 | System and methods for power generation |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US201562199958P | 2015-07-31 | 2015-07-31 | |
US15/225,801 US10283966B2 (en) | 2015-07-31 | 2016-08-01 | System and methods for power generation |
Related Child Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US16/370,367 Continuation US20190229534A1 (en) | 2015-07-31 | 2019-03-29 | System and methods for power generation |
Publications (2)
Publication Number | Publication Date |
---|---|
US20170133852A1 true US20170133852A1 (en) | 2017-05-11 |
US10283966B2 US10283966B2 (en) | 2019-05-07 |
Family
ID=58663866
Family Applications (2)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US15/225,801 Active 2037-05-24 US10283966B2 (en) | 2015-07-31 | 2016-08-01 | System and methods for power generation |
US16/370,367 Abandoned US20190229534A1 (en) | 2015-07-31 | 2019-03-29 | System and methods for power generation |
Family Applications After (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US16/370,367 Abandoned US20190229534A1 (en) | 2015-07-31 | 2019-03-29 | System and methods for power generation |
Country Status (1)
Country | Link |
---|---|
US (2) | US10283966B2 (en) |
Cited By (16)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20170133858A1 (en) * | 2015-11-09 | 2017-05-11 | General Electric Company | Power system for offshore applications |
US20180048157A1 (en) * | 2016-08-15 | 2018-02-15 | General Electric Company | Power generation system and related method of operating the power generation system |
US20180123384A1 (en) * | 2016-10-31 | 2018-05-03 | Keppel Offshore & Marine Technology Centre Pte Ltd | Power storage and supply method and system for a drilling rig |
US20180171977A1 (en) * | 2015-06-26 | 2018-06-21 | Vestas Wind Systems A/S | Increasing active power from a wind turbine |
WO2019023230A2 (en) | 2017-07-24 | 2019-01-31 | Suntech Drive, Llc | Solar pv and ac source power blending controller |
CN110425009A (en) * | 2019-07-10 | 2019-11-08 | 上海柯来浦能源科技有限公司 | Metal hydride Hydrogen Energy power generation electrical system and electricity-generating method |
US20190359064A1 (en) * | 2018-05-24 | 2019-11-28 | Hamilton Sundstrand Corporation | Electrical power system including energy storage modules and shared system controller |
US10889288B2 (en) * | 2017-12-31 | 2021-01-12 | Hyliion Inc. | Electric drive controller adaptation to through-the-road (TTR) coupled primary engine and/or operating conditions |
CN112689598A (en) * | 2018-09-12 | 2021-04-20 | 赛峰集团 | Hybrid propulsion assembly for an aircraft |
WO2021168214A1 (en) * | 2020-02-20 | 2021-08-26 | Velocity Magnetics, Inc. | Method, system, and computer program product for uninterrupted power using an array of ultra-capacitors |
US11322942B2 (en) * | 2017-10-12 | 2022-05-03 | Schlumberger Technology Corporation | Electrical power generation and distribution system with power recovery and regeneration |
WO2022272279A1 (en) * | 2021-06-23 | 2022-12-29 | Tecogen Inc. | Hybrid power system with electric generator and auxiliary power source |
US20230053593A1 (en) * | 2020-01-23 | 2023-02-23 | Innio Jenbacher Gmbh & Co Og | Power system |
US20230198295A1 (en) * | 2021-12-20 | 2023-06-22 | Schlumberger Technology Corporation | Power Management at a Wellsite |
US11735926B2 (en) | 2017-07-24 | 2023-08-22 | Premier Energy Holdings, Inc. | Solar PV and AC source power blending controller |
US11920438B2 (en) * | 2019-10-17 | 2024-03-05 | Schlumberger Technology Corporation | Intelligent power management system |
Families Citing this family (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US10283966B2 (en) * | 2015-07-31 | 2019-05-07 | Bluvert Technologies Ltd. | System and methods for power generation |
DE102017207102A1 (en) * | 2017-03-13 | 2018-09-13 | Bayerische Motoren Werke Aktiengesellschaft | Stationary storage for temporary storage of electrical energy in an electrical supply network and operating method and retrofit module for the stationary storage |
US10998732B2 (en) * | 2019-03-20 | 2021-05-04 | Caterpillar Inc. | System and method for diverse multi-source energy management |
US11697986B2 (en) | 2020-09-04 | 2023-07-11 | Schlumberger Technology Corporation | Power management at a wellsite |
US20220094174A1 (en) * | 2020-09-21 | 2022-03-24 | China University Of Petroleum Blue Sky(Qingdao) Petroleum Technology Co.,Ltd | Multi-source microgrid power supply system in oil well area |
Citations (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20120267957A1 (en) * | 2011-04-20 | 2012-10-25 | Czarnecki Neil A | Transfer Switch For Automatically Switching Between Alternative Energy Source And Utility Grid |
Family Cites Families (20)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
AP1042A (en) | 1996-12-20 | 2002-02-08 | Manuel Dos Santos Da Ponte | Hybrid generator apparatus. |
US6351692B1 (en) | 2000-10-24 | 2002-02-26 | Kohler Co. | Method and apparatus for configuring a genset controller for operation with particular gensets |
US6879053B1 (en) | 2002-10-22 | 2005-04-12 | Youtility, Inc. | Transformerless, load adaptive speed controller |
US20040084965A1 (en) | 2002-10-22 | 2004-05-06 | Welches Richard Shaun | Hybrid variable speed generator/uninterruptible power supply power converter |
EP1676023B1 (en) | 2003-10-06 | 2018-04-04 | PowerSys, LLC | Power generation systems and methods of generating power |
US20080203734A1 (en) | 2007-02-22 | 2008-08-28 | Mark Francis Grimes | Wellbore rig generator engine power control |
US7605497B2 (en) | 2007-06-08 | 2009-10-20 | Gm Global Technology Operations, Inc. | Two-source inverter |
US7980905B2 (en) * | 2007-11-25 | 2011-07-19 | C-Mar Holdings, Ltd. | Method and apparatus for providing power to a marine vessel |
US8987939B2 (en) | 2007-11-30 | 2015-03-24 | Caterpillar Inc. | Hybrid power system with variable speed genset |
US20090195074A1 (en) | 2008-01-31 | 2009-08-06 | Buiel Edward R | Power supply and storage device for improving drilling rig operating efficiency |
US20090312885A1 (en) | 2008-06-11 | 2009-12-17 | Buiel Edward R | Management system for drilling rig power supply and storage system |
US8143732B2 (en) | 2008-12-15 | 2012-03-27 | Caterpillar Inc. | Stationary genset power system having turbo-compounding |
US8022572B2 (en) | 2009-04-22 | 2011-09-20 | General Electric Company | Genset system with energy storage for transient response |
JP5320311B2 (en) | 2010-01-18 | 2013-10-23 | 三菱重工業株式会社 | Variable speed generator and control method thereof |
WO2012135258A2 (en) | 2011-03-29 | 2012-10-04 | Glacier Bay, Inc. | Generator |
SG11201400059UA (en) | 2011-08-19 | 2014-03-28 | Regen Technologies Pty Ltd | A power management system and method for optimizing fuel consumption |
US20140152007A1 (en) | 2012-12-05 | 2014-06-05 | Deif A/S | Managing Efficiency of a Pool of Engine-Driven Electric Generators |
US8946915B2 (en) | 2013-03-13 | 2015-02-03 | Caterpillar Inc. | Adaptive variable speed genset control |
US9450433B2 (en) | 2013-05-22 | 2016-09-20 | Eco-H Technologies Inc. | Method and system for controlling a portable power system |
US10283966B2 (en) * | 2015-07-31 | 2019-05-07 | Bluvert Technologies Ltd. | System and methods for power generation |
-
2016
- 2016-08-01 US US15/225,801 patent/US10283966B2/en active Active
-
2019
- 2019-03-29 US US16/370,367 patent/US20190229534A1/en not_active Abandoned
Patent Citations (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20120267957A1 (en) * | 2011-04-20 | 2012-10-25 | Czarnecki Neil A | Transfer Switch For Automatically Switching Between Alternative Energy Source And Utility Grid |
Cited By (28)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20180171977A1 (en) * | 2015-06-26 | 2018-06-21 | Vestas Wind Systems A/S | Increasing active power from a wind turbine |
US10451038B2 (en) * | 2015-06-26 | 2019-10-22 | Vestas Wind Systems A/S | Increasing active power from a wind turbine |
US10008856B2 (en) * | 2015-11-09 | 2018-06-26 | General Electric Company | Power system for offshore applications |
KR20180081762A (en) * | 2015-11-09 | 2018-07-17 | 제네럴 일렉트릭 컴퍼니 | Power systems for marine applications |
KR102609347B1 (en) | 2015-11-09 | 2023-12-01 | 제네럴 일렉트릭 컴퍼니 | Power systems for marine applications |
US20170133858A1 (en) * | 2015-11-09 | 2017-05-11 | General Electric Company | Power system for offshore applications |
US20180048157A1 (en) * | 2016-08-15 | 2018-02-15 | General Electric Company | Power generation system and related method of operating the power generation system |
US10797510B2 (en) * | 2016-10-31 | 2020-10-06 | Keppel Offshore & Marine Technology Centre Pte Ltd | Power storage and supply method and system for a drilling rig |
US20180123384A1 (en) * | 2016-10-31 | 2018-05-03 | Keppel Offshore & Marine Technology Centre Pte Ltd | Power storage and supply method and system for a drilling rig |
WO2019023230A3 (en) * | 2017-07-24 | 2019-07-18 | Suntech Drive, Llc | Solar pv and ac source power blending controller |
WO2019023230A2 (en) | 2017-07-24 | 2019-01-31 | Suntech Drive, Llc | Solar pv and ac source power blending controller |
US11171486B2 (en) | 2017-07-24 | 2021-11-09 | Premier Energy Holdings, Inc. | Solar PV and AC source power blending controller |
US11735926B2 (en) | 2017-07-24 | 2023-08-22 | Premier Energy Holdings, Inc. | Solar PV and AC source power blending controller |
US11322942B2 (en) * | 2017-10-12 | 2022-05-03 | Schlumberger Technology Corporation | Electrical power generation and distribution system with power recovery and regeneration |
US10889288B2 (en) * | 2017-12-31 | 2021-01-12 | Hyliion Inc. | Electric drive controller adaptation to through-the-road (TTR) coupled primary engine and/or operating conditions |
US20190359064A1 (en) * | 2018-05-24 | 2019-11-28 | Hamilton Sundstrand Corporation | Electrical power system including energy storage modules and shared system controller |
US11870249B2 (en) * | 2018-05-24 | 2024-01-09 | Hamilton Sundstrand Corporation | Electrical power system including energy storage modules and shared system controller |
CN112689598A (en) * | 2018-09-12 | 2021-04-20 | 赛峰集团 | Hybrid propulsion assembly for an aircraft |
US11932408B2 (en) | 2018-09-12 | 2024-03-19 | Safran | Hybrid propulsion assembly for aircraft |
CN110425009A (en) * | 2019-07-10 | 2019-11-08 | 上海柯来浦能源科技有限公司 | Metal hydride Hydrogen Energy power generation electrical system and electricity-generating method |
US11920438B2 (en) * | 2019-10-17 | 2024-03-05 | Schlumberger Technology Corporation | Intelligent power management system |
US20230053593A1 (en) * | 2020-01-23 | 2023-02-23 | Innio Jenbacher Gmbh & Co Og | Power system |
US11955837B2 (en) * | 2020-01-23 | 2024-04-09 | Innio Jenbacher Gmbh & Co Og | Power system |
WO2021168214A1 (en) * | 2020-02-20 | 2021-08-26 | Velocity Magnetics, Inc. | Method, system, and computer program product for uninterrupted power using an array of ultra-capacitors |
WO2022272279A1 (en) * | 2021-06-23 | 2022-12-29 | Tecogen Inc. | Hybrid power system with electric generator and auxiliary power source |
US11936327B2 (en) | 2021-06-23 | 2024-03-19 | Tecogen Inc. | Hybrid power system with electric generator and auxiliary power source |
US20230198295A1 (en) * | 2021-12-20 | 2023-06-22 | Schlumberger Technology Corporation | Power Management at a Wellsite |
US11942781B2 (en) * | 2021-12-20 | 2024-03-26 | Schlumberger Technology Corporation | Power management at a wellsite |
Also Published As
Publication number | Publication date |
---|---|
US10283966B2 (en) | 2019-05-07 |
US20190229534A1 (en) | 2019-07-25 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US10283966B2 (en) | System and methods for power generation | |
US8987939B2 (en) | Hybrid power system with variable speed genset | |
Sebastián et al. | Control and simulation of a flywheel energy storage for a wind diesel power system | |
KR100519861B1 (en) | Island network and method for operating of an island network | |
JP2013039028A (en) | Hybrid electric generator set | |
US8227935B2 (en) | Hybrid power supply device | |
US9312699B2 (en) | Island grid power supply apparatus and methods using energy storage for transient stabilization | |
US9628010B2 (en) | Power distribution systems comprising variable frequency AC generator | |
Braun | Reactive power supply by distributed generators | |
US6879053B1 (en) | Transformerless, load adaptive speed controller | |
US20090195074A1 (en) | Power supply and storage device for improving drilling rig operating efficiency | |
KR102249662B1 (en) | Marine integrated power control management system | |
PL210291B1 (en) | Separate network and method for operating a separate network | |
WO2009150413A1 (en) | Management system for drilling rig power supply and storage system | |
US20160065003A1 (en) | Power system and method | |
CN108054967B (en) | Brushless double-fed motor-based diesel power generation system and control method thereof | |
JP4376089B2 (en) | Gas engine power generation equipment | |
KR101753667B1 (en) | A Flywheel Energy Storage System Based on Battery for Microgrid Control | |
JP2011256827A (en) | Power supply system | |
Vijay et al. | Standalone and grid connected operations of a SynRG based WECS with BESS | |
CN116599094A (en) | Energy storage black start system and control method thereof | |
CN113852318A (en) | New energy power generation direct drive system | |
Koczara et al. | Energy management and power flow of decoupled generation system for power conditioning of renewable energy sources | |
Sebastián et al. | Sizing and simulation of a low cost flywheel based energy storage system for wind diesel hybrid systems | |
Sebastián | Review on Dynamic Simulation of Wind Diesel Isolated Microgrids. Energies 2021, 14, 1812 |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
AS | Assignment |
Owner name: BLUVERT TECHNOLOGIES LTD., CANADA Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:MACDONALD, DON;REEL/FRAME:045188/0484 Effective date: 20180218 |
|
STPP | Information on status: patent application and granting procedure in general |
Free format text: PUBLICATIONS -- ISSUE FEE PAYMENT VERIFIED |
|
STCF | Information on status: patent grant |
Free format text: PATENTED CASE |
|
MAFP | Maintenance fee payment |
Free format text: PAYMENT OF MAINTENANCE FEE, 4TH YR, SMALL ENTITY (ORIGINAL EVENT CODE: M2551); ENTITY STATUS OF PATENT OWNER: SMALL ENTITY Year of fee payment: 4 |